Hi number6,
First of all I have not been able to verify that the original
House on Haunted Hill film is in the public domain, and if so, why. I know the Wikipedia entry says it is, but the citations in the article don't confirm this. The circumstances matter: if copyright never camer into existence because the film was not registered or failed to contain a proper copyright notice, then I think it would fall to be treated as with the
Night of the Living Dead. However, if the film was registered for its first 28 year period, but the registration was not renewed as you suggest, even though this would mean that the initial copyright term was running at the time the 1976 Copyright came into effect, copyright would have ended on 31 December 1989 (see this
Wikipedia article for an explanation).
So let's proceed on the basis that, in the USA, the film was first registered for copyright but because it wasn't re-registered, it's now in the public domain there. And for the sake of clarity, what follows only applies to the original black and white version of the film, not any subsequent colorised versions.
IMDB says the UK release was September 1959, whereas the US release was 14 February 1959, so as the UK release was not within 30 days of the release in the country of origin, it would not have been treated as if the film had originated in the UK. A strict interpretation of
section 13B(7) would mean that only the 28 year term provided for by US law (ie the initial registration period) would apply in the UK. As you have seen, Nick Cooper says that the existence of the 1891 bilateral agreement between the US and the UK would have overridden this provision; I'm not so sure. Because we don't have the text of the agreement, or more importantly, the text of the Order in Council which brought the treaty into UK law, we can't be sure whether the treaty meant that a US work would get the same treatement as a UK work, or that UK law would only provide the same treatment as was available on the originating country, provided that did not exceed the term available in the UK.
The best guidance on this is to be found in
section 29 of the 1911 Copyright Act. However it is worth noting that this section only applies to literary, dramatic, musical or artistic works. The key parts are to be found in sub-section (1)(a):
His Majesty may, by Order in Council, direct that this Act (except such parts, if any, thereof as may be specified in the Order) shall apply --
(a) to works first published in a foreign country to which the order relates, in like manner as if they were first published within the parts of His Majesty's dominions to which this Act extends.
Several provisos then followed, the most relevant being sub-sub-section (ii) which says:
the Order in Council may provide that the term of copyright within such parts of His Majesty's dominions as aforesaid shall not exceed that conferred by the law of the country to which the Order relates.
For obvious reasons the 1911 Act does not mention cinematograph films (or sound recordings and broadcasts) so we cannot know whether an Order in Council from that era would have been carefully worded so as to restrict its effect just to literary, dramatic, musical or artistic works, or to 'works' in general.
The 1956 Copyright Act, which would have applied to this particular film, covers some of the same ground in its
section 32. This time we know that these provisions also apply to cinematograph films. However the explicit proviso that an Order in Council may restrict the operation of UK law so that the term does not exceed the term available in the country of origin has been omitted. It just says that an Order may specify exceptions or modifications to the general rule. Of course we are not concerned with any Orders in Councils which were made after the 1956 Act, only the one made to reflect the 1891 Treaty. Unhelpfully, the remainder of the 1956 Act contains no corresponding provision of the sort we find in section 13B (7) of the 1988 CDPA. In other words there is considerable uncertainty about whether
House on Haunted Hill could expect the full UK term of 50 years from its UK release (later to become the lifetime of its director etc plus 70 years), or just the original 28 years of its US copyright term. In the absence of the text of the original Order in Council, and a strict reading of the 1956 Act, I would tend to think it was probably the former.
I'm sorry I can't provide a more precise answer.