Jack Palance and director Robert Aldrich had worked together with distinction on two previous occasions - "Attack!" and "The Big Knife" - but fell out most acrimoniously during the making of this film. Aldrich later remarked wryly that it was probably unwise for any director to work more than twice with an actor as volatile as Palance, but nonetheless sought him out yet again a few years later when Palance was offered the role of Archer Maggot in "The Dirty Dozen". It seemed there might be a reconciliation at last, but Palance dropped out at the last minute (because of illness, some sources have claimed) and the part was taken over by Telly Savalas.
Gerhard Rabiger, a German bomb expert, was hired to instruct Jeff Chandler and Jack Palance in defusing techniques. Rabiger had defused as many as 20 bombs a day in Berlin just after the end of WWII. Even while this film was being made, bombs were still being discovered in Berlin at a rate of about two a week.
Director Robert Aldrich had his name taken off the credits as producer because the studio cut a half-hour out of the picture without telling him, and he believed that unless they put that footage back in, the film made no sense. The studio refused, so Aldrich had his name taken off as producer.
Although Robert Aldrich made this film before "The Angry Hills", it was not released until several months later in the UK. In the US, both films were released in the same month, in both cases later than in Britain.
Supposedly, if the bomb explodes, you don't feel pain because the speed of the explosion is faster than the electrical system of the body.