Are executives at 21st Century Fox (FOXA) afraid audiences will forget about its Marvel properties? It sure looks like it, Fool contributor Tim Beyers says in the following video.

How so? Shortly after Walt Disney (DIS 1.51%) and Marvel released a new trailer for Captain America: The Winter Soldier, Fox responded with six seconds of teaser footage of X-Men: Days of Future Past, which is due in May 2014. The studio has since released a full trailer.

There's a lot riding on Days of Future Past, Tim says. The seventh installment in Fox's series of X-films, Days bridges the events of the last team film -- the largely unsuccessful X-Men: First Class -- and this summer's The Wolverine, a lower-budget epic that earned a respectable $405.6 million worldwide. Days could put up similar numbers if word of mouth builds ahead of release. Strong buzz for Captain America, which releases a month earlier, could get in the way.

Should Fox investors temper expectations? Or will X-Men: Days of Future Past kick off a string of new mutant-themed Marvel films from the studio? Tim addresses these questions in the video. Please watch now, and then leave a comment to let us know what you think.